CN108340766B

CN108340766B - Hybrid power system, vehicle and control method thereof

Info

Publication number: CN108340766B
Application number: CN201810004389.5A
Authority: CN
Inventors: 席军强; 李麟
Original assignee: Beijing Institute of Technology BIT
Current assignee: Beijing Institute of Technology BIT
Priority date: 2018-01-03
Filing date: 2018-01-03
Publication date: 2021-06-04
Anticipated expiration: 2038-01-03
Also published as: CN108340766A

Abstract

The present invention relates to a hybrid power system, a vehicle and a control method thereof. The hybrid system includes an engine, a dual mechanical port electric machine, a battery pack, a first transmission, and a second transmission. The dual mechanical port motor includes an inner rotor, an outer rotor and a stator; the output shaft of the engine is connected with the input shaft of the first transmission through the inner rotor shaft; the output shaft of the outer rotor is connected with the input shaft of the second transmission; the stator is connected to the battery pack Electrical connection; the output shafts of the first transmission and the second transmission are both used for connection with the wheels. Since the engine and the outer rotor of the dual-mechanical-port motor are two completely independent power sources, which are not constrained to each other, the present invention realizes the decoupling control of the power required by the engine and the reserve power under normal working conditions, and reduces the power consumption of the engine and the power reserve. After the volume and weight of the transmission mechanism, the present invention realizes the optimization of the transmission system in the three dimensions of volume, weight and the coverage rate of the reserve power through the decoupling of the reserve power.

Description

Hybrid power system, vehicle and control method thereof

Technical Field

The invention relates to the technical field of vehicles, in particular to a hybrid power system, a vehicle and a control method thereof.

Background

In order to meet the requirements of high maneuverability and wider working condition adaptability of heavy-duty wheeled vehicles, the main method is to improve the reserve power of an engine at present. However, the increased reserve power is not efficient in practical use, and causes a series of problems of the power transmission system, such as large volume, increased weight, and heat dissipation. In addition, in order to improve the power density and specific power of a power transmission system of a heavy-duty vehicle, the currently common method is to improve the rotating speed of an engine as much as possible, so that the torque requirement of the power transmission system can be reduced, and the volume of the power transmission system can be reduced.

Disclosure of Invention

In view of the above analysis, the present invention aims to provide a hybrid system, a vehicle and a control method thereof, so as to solve the problem that the volume of a transmission system is increased in order to increase the reserve power of the existing vehicle.

The purpose of the invention is mainly realized by the following technical scheme:

in one aspect, the present disclosure provides a hybrid system, comprising: the system comprises an engine, a double-mechanical-port motor, a battery pack, a first transmission and a second transmission; the double mechanical port motor comprises an inner rotor, an outer rotor and a stator; an output shaft of the engine is connected with a first end of the inner rotor rotating shaft, and a second end of the inner rotor rotating shaft is connected with an input shaft of the first transmission; an output shaft of the outer rotor is connected with an input shaft of the second transmission; the stator is electrically connected with the battery pack; the output shafts of the first transmission and the second transmission are connected with wheels.

Further, the hybrid system further includes: a normally closed clutch; and the second end of the rotating shaft of the inner rotor is connected with the input shaft of the first transmission through a normally closed clutch.

Further, in the above hybrid system, the first transmission includes: the first input shaft, the first output shaft, the first gear mechanism, the third gear mechanism, the fifth gear mechanism and the reverse gear mechanism; the driving gears of the first gear mechanism, the third gear mechanism, the fifth gear mechanism and the reverse gear mechanism are all connected with the first input shaft; the driven gears of the first gear mechanism, the third gear mechanism, the fifth gear mechanism and the reverse gear mechanism are all arranged with the second input shaft and are selectively connected with the first output shaft through corresponding joint sleeves.

Further, in the above hybrid system, the second transmission includes: the second input shaft, the second output shaft, the second gear mechanism and the fourth gear mechanism; the driving gears of the second gear mechanism and the fourth gear mechanism are connected with the second input shaft; the driven gears of the two-gear mechanism and the four-gear mechanism are coaxially arranged with the second output shaft and selectively connected with the second output shaft through corresponding joint sleeves.

In another aspect, the present invention further provides a control method of a hybrid system, including the steps of; judging the working condition of the vehicle provided with the hybrid power system; when the vehicle is in an accelerating or climbing working condition, the engine is controlled to drive the inner rotor to operate, and the battery pack drives the outer rotor to operate simultaneously.

Further, in the control method of the hybrid system, when a first transmission of the vehicle is in a gear shifting working condition, the battery pack is controlled to drive the outer rotor to operate; and when a second transmission of the vehicle is in a gear shifting working condition, controlling the engine to drive the inner rotor to operate.

Further, in the control method of the hybrid power system, when the vehicle is in a parking power generation working condition, all gear engaging sleeves of the first transmission and the second transmission are controlled to be disconnected, the inner rotor and the outer rotor work in a generator mode simultaneously, and the inner rotor and the outer rotor are controlled to work simultaneously to generate power; or when the vehicle is in a working condition of charging the battery pack in the running process, all gear engaging sleeves of the second transmission are controlled to be disconnected, the first transmission is controlled to be engaged, the inner rotor and the outer rotor work in a generator mode simultaneously, and the inner rotor and the outer rotor are controlled to operate simultaneously to generate power; or when the vehicle is in a braking and decelerating working condition, all gear engaging sleeves of the first transmission are controlled to be disconnected, the second transmission is controlled to be engaged, the outer rotor works in a generator mode, and kinetic energy of the vehicle is utilized to drive the outer rotor to generate power and recover energy.

Further, in the control method of the hybrid system, when the vehicle is in an engine starting working condition, all gear engaging sleeves of the first transmission are controlled to be disconnected, and the inner rotor is controlled to operate to start the engine.

Further, in the control method of the hybrid system, when the vehicle is in a hill start condition of more than 30 degrees, the normally closed clutch is sequentially controlled to be disconnected, the inner rotor is sequentially controlled to rotate to start the engine, the corresponding gear in the first transmission is engaged, the normally closed clutch is engaged, and the inner rotor and the outer rotor are simultaneously operated.

Because the engine and the battery pack are two completely independent power sources and are not mutually constrained, the invention realizes the decoupling control of the power required by the engine under the common working condition and the reserve power, reduces the volume and the weight of the engine and a subsequent transmission mechanism, can realize the optimization of a vehicle power transmission system on three dimensions of the volume, the weight and the reserve power working condition coverage rate, namely the reserve power utilization rate, and can design the decoupling rate of the reserve power according to the use of the vehicle, thereby being convenient and flexible and having wide application range. The system has simple structure and low cost.

In another aspect, the invention also provides a vehicle provided with any one of the hybrid power systems described above.

Due to the effects described above in the hybrid system, the vehicle having the hybrid system also has corresponding technical effects.

In the invention, the technical schemes can be combined with each other to realize more preferable combination schemes. Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The drawings are only for purposes of illustrating particular embodiments and are not to be construed as limiting the invention, wherein like reference numerals are used to designate like parts throughout.

Fig. 1 is a schematic structural diagram of a hybrid power system according to an embodiment of the present invention.

Detailed Description

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate preferred embodiments of the invention and together with the description, serve to explain the principles of the invention and not to limit the scope of the invention.

The embodiment of the power system comprises:

referring to fig. 1, a preferred structure of a hybrid system provided by an embodiment of the present invention is shown. As shown, the system includes: the hybrid power system comprises an engine 1, a double mechanical port motor 2, a battery pack 3, a first transmission 4 and a second transmission 5.

The double mechanical port motor 2 comprises an inner rotor 21, an outer rotor 22 and a stator 23, wherein the inner rotor 21 and the outer rotor 22 can independently operate. The output shaft of the engine 1 is connected to a first end (left end in fig. 1) of the rotating shaft of the inner rotor 21, and a second end (right end in fig. 1) of the rotating shaft of the inner rotor 21 is coaxially connected to the input shaft of the first transmission 4. The engine 1 drives the inner rotor 21 to rotate, the inner rotor 21 drives the input shaft of the first transmission 4 to rotate, and the engine 1 provides power for the first transmission 4. An output shaft of the outer rotor 22 can be connected with an input shaft of the second transmission 5 through gear transmission, the outer rotor 22 drives the input shaft of the second transmission 5 to rotate, the battery pack 3 is electrically connected with the stator 23 through the inverter 9, and the outer rotor 22 provides power for the second transmission 5. The battery pack 3 supplies power to the double mechanical port motors 2 through the inverter 9, and the inner rotor 21 and the outer rotor 22 of the double mechanical port motors need to be supplied with power respectively. In addition, the outer rotor 22 may also charge the battery pack 3.

The output shafts of the first transmission 4 and the second transmission 5 may be connected to the input shaft of a differential 7 through a gear mechanism, two output ends of the differential 7 are connected to two half shafts 8, respectively, and output ends of the two half shafts 8 are connected to wheels to drive the wheels.

In specific implementation, the output shaft of the outer rotor 22 and the second transmission 5, and the output shafts of the first transmission 4 and the second transmission 5 and the input shaft of the differential 7 may be connected through a gear mechanism, or may be connected through other transmission mechanisms known to those skilled in the art.

The present embodiment has two independent power sources, one is an engine 1 and one is a dual mechanical port motor 2. The engine 1 drives the first transmission 4 to operate through the inner rotor 21, and the first transmission 4 transmits power to the half shaft 8 through the differential 7 to drive wheels. The battery pack 3 supplies power to the stator 23, the stator 23 drives the outer rotor 22 to rotate, the outer rotor 22 drives the second transmission 5 to operate, and the second transmission 5 also transmits power to the half shaft 8 through the differential 7 so as to drive wheels.

In specific implementation, one of the outer rotors of the engine 1 and the two mechanical port motors 2 can be used as a conventional power source, and the other can be used as a reserve power source to provide reserve power.

This embodiment is provided with three fender mechanism and a reverse gear mechanism that advances in first derailleur 4, is provided with two fender mechanisms that advance in second derailleur 5, specifically is:

the first transmission 4 includes: a first input shaft 41, a first output shaft 42, a first gear mechanism 43, a third gear mechanism 44, a fifth gear mechanism 45, and a reverse gear mechanism 46. The driving gears of the first gear mechanism 43, the third gear mechanism 44, the fifth gear mechanism 45 and the reverse gear mechanism 46 are all connected with the first input shaft 41, and the driven gears of the first gear mechanism 43, the third gear mechanism 44, the fifth gear mechanism 45 and the reverse gear mechanism 46 are all coaxially arranged with the first output shaft 42 but not connected with the same. In a specific embodiment, the first engaging sleeve 4A, the third engaging sleeve 4B, the fifth engaging sleeve 4C and the reverse engaging sleeve 4D can control the first gear mechanism 43, the third gear mechanism 44, the fifth gear mechanism 45 and the reverse gear mechanism 46 to operate, respectively, to transmit power to the first output shaft 42.

The second transmission 5 includes: a second input shaft 51, a second output shaft 52, a second gear mechanism 53, and a fourth gear mechanism 54. The driving gears of the second gear mechanism 53 and the fourth gear mechanism 54 are both connected to the second input shaft 51, and the driven gears of the second gear mechanism 53 and the fourth gear mechanism 54 are both coaxially disposed with the second output shaft 52 but not connected thereto, but those skilled in the art will understand that each gear mechanism should be provided with a joint sleeve, and the joint sleeve of each gear mechanism is alternatively in meshed connection with the second output shaft 52, so as to connect the driven gear of the corresponding gear mechanism with the second output shaft 52. In practice, it will be understood by those skilled in the art that the second and fourth

engaging sleeves

5A and 5B can control the second and

fourth gears

53 and 54 to transmit power to the second output shaft 52.

It should be noted that the gear setting conditions of the first transmission 4 and the second transmission 5 are only schematically presented in this embodiment, and in a specific implementation, the specific gear setting of the first transmission 4 and the second transmission 5 may be determined according to actual conditions, and this embodiment does not limit this.

Because the engine 1 and the double mechanical port motor 2 are two completely independent power sources, one provides conventional power and the other provides reserve power, and are not mutually constrained, the decoupling control of the power required by the engine under a common working condition and the reserve power is realized, the volume and the weight of the engine and a subsequent transmission mechanism are reduced, the vehicle power transmission system can be optimized in three dimensions of volume, weight and reserve power working condition coverage rate, namely reserve power utilization rate, by decoupling the reserve power, and the decoupling rate of the reserve power can be designed according to the use of the vehicle, so that the vehicle power transmission system is convenient and flexible and has a wide application range. The system has simple structure, low cost, high transmission efficiency and high power density.

In addition, because the two power sources in the embodiment can work independently and also can work together, the output power and the speed of the two power sources can be controlled respectively, the dynamic property and the fuel economy of the vehicle are improved, and the device is particularly suitable for heavy vehicles and has more remarkable effect. Through experiments, the power of the power-driven vehicle can be improved by 60% under the condition that the volume and the weight of the transmission system are equivalent to those of the conventional vehicle. And when one path of power source breaks down, the other path of power source can ensure the normal operation of the vehicle, thereby improving the fault-tolerant rate of the vehicle and ensuring the driving safety.

In this embodiment, when the first transmission 4 is shifted, the power required for vehicle operation may be continuously provided by the outer rotor 22 of the dual mechanical port motor 2; the power required for vehicle operation may be continuously provided by the engine 1 when the second transmission 5 is shifted. It can be seen that the power system in the embodiment has no problem of power interruption when shifting gears, and ensures the smooth running of the vehicle.

In the above embodiment, the method may further include: the clutch 6 is normally closed. Wherein, the second end of the rotating shaft of the inner rotor 21 can be connected with the input shaft of the first speed changer 4 through the normally closed clutch 6.

When the vehicle works in a large-angle slope starting condition, for example, a slope starting condition of more than 30 degrees, the vehicle cannot be started only by the outer rotor 22 of the double-mechanical-port motor 2, at this time, the normally-closed clutch 6 needs to be disconnected, the engine 1 is started by the inner rotor 21, then the first transmission 4 is connected, finally the normally-closed clutch 6 is connected, and the engine 1 and the outer rotor 23 drive the vehicle together.

In the embodiment, only one normally-closed clutch is arranged between the inner rotor 21 and the first transmission 4, so that the vehicle can be started under a large-angle slope starting working condition, the structure and the size of the transmission are simplified, and the cost is reduced.

The embodiment of the control method comprises the following steps:

the embodiment of the invention provides a control method of a hybrid power system, which is used for controlling the hybrid power system to operate under different working conditions, and the specific operation process of each working condition is explained below.

The operation of the hybrid system is controlled according to the working condition of the vehicle, and the following detailed description is respectively provided for different working conditions.

When the vehicle is in an accelerating or climbing condition, the engine 1 and the outer rotor 22 are controlled to run simultaneously. The method specifically comprises the following steps: when the vehicle is in a transient acceleration or climbing working condition, the engine 1 can drive the inner rotor 21 to operate, and meanwhile, the battery pack 3 can drive the outer rotor 22 to operate, so that the inner rotor 21 and the outer rotor 22 simultaneously work at the maximum power, and the inner rotor 21 and the outer rotor 22 jointly output power to the differential 7 to jointly provide power for the vehicle.

When the vehicle is in a gear shifting condition, two conditions are divided: in the first case, when the first transmission 4 is shifted, the power required by the vehicle can be provided by the battery pack 3 driving the outer rotor 22 of the dual mechanical port motor 2, and the engine 1 adjusts its rotation speed, so that the rotation speeds of the input shaft and the output shaft of the first transmission 4 are matched, and the first engaging sleeve 4A, the third engaging sleeve 4B, the fifth engaging sleeve 4C and the reverse engaging sleeve 4D of the first transmission 4 can be engaged smoothly to complete the shifting. The second situation is that the second transmission 5 shifts gears, and similarly, at this time, the power required by the vehicle can be completely provided by the engine 1, and the rotation speed of the outer rotor 22 of the dual mechanical port motor 2 is adjusted, so that the rotation speeds of the input shaft and the output shaft of the second transmission 5 are matched, and the second engaging sleeve 5A and the fourth engaging sleeve 5B of the second transmission 5 can be smoothly engaged to complete the shifting.

When the vehicle stops to generate power, all the engaging sleeves in the first transmission 4 and the second transmission 5 are disconnected, and the inner rotor 21 of the double-mechanical-port motor 2 and the output shaft of the engine 1 are fixedly connected to the input shaft of the first transmission 4. At this time, the engine 1 rotates the inner rotor 21 relative to the outer rotor 22, and generates electric power. Meanwhile, the outer rotor 22 is acted by the electromagnetic force of the inner rotor 21, and also rotates relative to the stator 23 of the dual mechanical port motor 2, so as to generate electric energy again to charge the battery pack 3. In this case, the inner and outer rotors of the dual mechanical port motor 2 can be regarded as two generators operating.

When the vehicle needs to charge the battery pack 3 during running, both the second and

fourth clutches

5A, 5B of the second transmission 5 are disconnected. The double mechanical port motor 2 is the same as a parking power generation mode, an inner rotor 21 and an outer rotor 22 of the double mechanical port motor work in a power generator mode at the same time, an engine 1 drives the inner rotor 21 and the outer rotor 22 to operate at the same time, and power is transmitted in two ways: one path of the power is transmitted to wheels through an inner rotor 21, a first transmission 4 and a differential mechanism 7 in sequence for the vehicle to run; the other path generates power through the inner rotor and the outer rotor of the double mechanical port motor 2 to charge the battery pack 3.

When the vehicle needs to start the engine 1, the four gear engaging sleeves of the first transmission 4 are all disconnected, the inner rotor 21 of the double mechanical port motor 2 is started, and the engine 1 is driven to start. After the engine 1 is started, the rotation speed of the engine is adjusted to enable the clutch sleeve of the gear needing to be connected in the first transmission 4 to be smoothly engaged.

When the vehicle is in a braking and decelerating working condition, all gear engaging sleeves of the first transmission 4 are controlled to be disconnected, the second transmission 5 is controlled to be engaged, the outer rotor 22 works in a generator mode, and the kinetic energy of the vehicle is utilized to drive the outer rotor 22 to generate electricity and recover energy. When the vehicle is driven forward, the external rotor 22 and the second transmission 2 are mechanically connected to output power to wheels. Similarly, when the vehicle is braked, the outer rotor 22 works in a generator mode, and at this time, the kinetic energy of the vehicle, through the torque generated by the friction force between the ground and the tire, is transmitted by the second transmission 2 to drive the outer rotor 22 to rotate, so that the generation resistance torque is overcome, electric energy is generated, and the battery pack 3 and the super capacitor are charged.

When the vehicle works in a slope starting condition of more than 30 degrees, the outer rotor 22 of the double-mechanical-port motor 2 is only used for starting the vehicle, and then the normally-closed clutch 6 is disconnected, the inner rotor 21 is used for starting the engine 1, then the first transmission 4 is connected, and finally the normally-closed clutch 6 is connected, and the engine 1 and the outer rotor 23 jointly drive the vehicle.

Because the two power sources in the embodiment can work independently or together, the output power and the speed of the two power sources can be controlled respectively, the dynamic property and the fuel economy of the vehicle are improved, and the two power sources are particularly suitable for heavy vehicles and have more remarkable effects. Through experiments, the power of the power-driven vehicle can be improved by 60% under the condition that the volume and the weight of the transmission system are equivalent to those of the conventional vehicle. And when one path of power source breaks down, the other path of power source can ensure the normal operation of the vehicle, thereby improving the fault-tolerant rate of the vehicle and ensuring the driving safety.

In the embodiment, when the first transmission 4 is shifted, the power required by the running of the vehicle is continuously provided by the outer rotor 22 of the double-mechanical-port motor 2; the power required for vehicle operation is continuously provided by the engine 1 when the second transmission 5 is shifted. It can be seen that the power system in the embodiment has no problem of power interruption when shifting gears, and ensures the smooth running of the vehicle.

The embodiment of the vehicle is as follows:

the embodiment of the invention also provides a vehicle which is provided with any one of the hybrid power systems. The specific implementation process of the hybrid power system may refer to the above description, and the detailed description of the embodiment is omitted here.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.

Claims

1. A hybrid power system, applied to a heavy-duty wheeled vehicle, characterized in that it comprises: an engine (1), a dual mechanical port motor (2), a battery pack (3), a first transmission (4) and a second a transmission (5) and an inverter (9); wherein the dual mechanical port motor (2) comprises an inner rotor (21), an outer rotor (22) and a stator (23) which are sequentially arranged from the inside to the outside; The inverter (9) is used for connecting the battery pack (3) and the stator (23);

The output shaft of the engine (1) is connected with the first end of the rotating shaft of the inner rotor (21), and the second end of the rotating shaft of the inner rotor (21) is connected with the input shaft of the first transmission (4). connect;

The output shaft of the outer rotor (22) is connected with the input shaft of the second transmission (5);

The stator (23) is electrically connected to the battery pack (3);

The output shafts of the first transmission (4) and the second transmission (5) are both used for driving wheels;

Also includes: a normally closed clutch (6); wherein, the second end of the rotating shaft of the inner rotor (21) is connected with the input shaft of the first transmission (4) through the normally closed clutch (6);

The first transmission (4) comprises: a first input shaft (41), a first output shaft (42), a first gear mechanism (43), a third gear mechanism (44), a fifth gear mechanism (45) and a reverse gear mechanism (46); wherein,

The driving gears of the first gear mechanism (43), the third gear mechanism (44), the fifth gear mechanism (45) and the reverse gear mechanism (46) are all in phase with the first input shaft (41). connect;

The driven gears of the first gear mechanism (43), the third gear mechanism (44), the fifth gear mechanism (45) and the reverse gear mechanism (46) are all connected to the first output shaft (42) Coaxially arranged, and selectively connected with the first output shaft (42) through a corresponding engagement sleeve;

The second transmission (5) comprises: a second input shaft (51), a second output shaft (52), a second gear mechanism (53) and a fourth gear mechanism (54); wherein,

The driving gears of the second gear mechanism (53) and the fourth gear mechanism (54) are both connected with the second input shaft (51);

The driven gears of the second gear mechanism (53) and the fourth gear mechanism (54) are coaxially arranged with the second output shaft (52), and can be selectively connected with the second output shaft through corresponding engagement sleeves The shaft (52) is connected;

The engine (1) and the dual mechanical port motor (2) are two completely independent power sources;

When the vehicle is in an acceleration or climbing condition, controlling the engine to drive the inner rotor to run, and the battery pack to drive the outer rotor to run simultaneously;

When the first transmission of the vehicle is in a shifting condition, controlling the battery pack to drive the outer rotor to operate; when the second transmission of the vehicle is in a shifting condition, controlling the engine to drive the inner rotor to operate;

When the vehicle is in the parking power generation condition, all the gear engagement sleeves of the first transmission and the second transmission are controlled to be disconnected, the inner rotor and the outer rotor work in the generator mode at the same time, and the inner rotor and the outer rotor are controlled to work in the generator mode at the same time. The outer rotor runs at the same time to generate electricity; or, when the vehicle is in the state of charging the battery pack during driving, all the gear engagement sleeves of the second transmission are controlled to be disconnected, the first transmission is controlled to be engaged, and the inner rotor and the outer rotor are simultaneously Work in the generator mode, and control the inner rotor and the outer rotor to run and generate electricity at the same time; or, when the vehicle is in the braking and deceleration condition, control all the gear engagement sleeves of the first transmission to be disconnected, and control the first transmission. The second transmission is engaged, the outer rotor works in generator mode, and the kinetic energy of the vehicle is used to drive the outer rotor to generate electricity and recover energy;

When the vehicle is in an engine-starting condition, controlling all gear engagement sleeves of the first transmission to be disconnected, and controlling the inner rotor to operate to start the engine;

When the vehicle is in a slope starting condition greater than 30 degrees, the normally closed clutch is controlled to be disconnected, the inner rotor is rotated to start the engine, the corresponding gear in the first transmission is engaged, the The normally closed clutch is engaged and the inner rotor and the outer rotor operate simultaneously.

2. A vehicle equipped with the hybrid system according to claim 1.